Quick tightening abutment lock

Abstract

An abutment lock utilized with an implant anchor which has a substantially smooth axial bore which may have longitudinal guide grooves formed therein. The abutment element has an insertion end which is also substantially smooth and which terminates in an oblique lower surface. A bore through the abutment allows a threaded bolt to engage a wedge nut having a cooperatively formed oblique surface and a plurality of guide protrusions such that rotation of the bolt urges the nut against the abutment oblique surfaces thereby urging the smooth surfaces of the nut and abutment into intimate surface to surface contact with the cylindrical wall of the anchor. The relatively large surface area in compressive contact between the abutment and the anchor resists movement between the components.

What is claimed is: 
     
       1. In an implant system for attaching prosthetic devices to the osseous structure of the body wherein an implant anchor is osseointegrated into the bone of a patient in a preprepared hole, the combination therewith comprising: a. an implant anchor having an axial bore which is divided into a plurality of regions including a terminal region within said anchor, including a smooth substantially cylindrical wall circumscribing said terminal region and a generally cylindrical entrant region circumscribing the bore at a coronal end of said anchor;   b. an abutment for connecting a prosthesis to said anchor and having an insertion end adapted for insertion into said bore at said coronal end of said anchor, said abutment having an internal bore and smooth outer walls at said insertion end and an oblique bearing surface formed transversely of said internal bore at insertion end; and,   c. means for connecting said abutment to said anchor by urging a locking element between said oblique bearing surface and said cylindrical wall.   
     
     
       2. The combination as defined in claim 1 wherein said means for connecting comprises a threaded member extending through said internal bore and threadedly engaging a wedge nut within said axial bore, such that rotation of said threaded member urges said wedge nut axially within said axial bore. 
     
     
       3. The combination as defined in claim 2 wherein said wedge nut includes a bearing surface formed obliquely to said threaded member for confronting engagement with said oblique bearing surface of said abutment such that rotation of said threaded member urges said wedge nut against said oblique bearing surface such that a component of the force applied in rotation of said threaded member is transferred to urge said nut and abutment insertion end laterally against said cylindrical walls. 
     
     
       4. The combination as defined in claim 3 wherein said threaded member has a laterally extending shoulder for engagement with a laterally extending seat formed in said abutment internal bore. 
     
     
       5. The combination as defined in claim 3 wherein said oblique bearing surface and said smooth outer wall define an included angle of about 35° at said insertion end. 
     
     
       6. The combination as defined in claim 3 wherein said threaded member includes means formed on an upper end thereof for engagement by a selected tool to impart rotation to said threaded member. 
     
     
       7. The combination as defined in claim 6 wherein said means for engagement comprises a drive socket formed in said threaded member. 
     
     
       8. The combination as defined in claim 6 wherein said means for engagement comprises a drive head formed on said threaded member. 
     
     
       9. The combination as defined in claim 3 wherein said wedge nut has a smooth outer wall such that maximum surface to surface contact is made between said wedge nut and said wall of said axial bore. 
     
     
       10. The combination as defined in claim 3 wherein said wedge nut has a plurality of angularly space protrusions formed thereon for engagement in selected one of a plurality of indexing grooves formed in said wall of said axial bore. 
     
     
       11. Apparatus for attaching a prosthesis to living tissue, comprising in combination, a. anchor means, having a generally longitudinally formed receptacle therein, insertable into a cavity formed in living bone tissue for osseointegration thereinto as an anchor for a prosthesis; and,   b. abutment means for connecting said anchor means to said prosthesis having a portion thereof insertable into said receptacle; and,   c. lock means for engaging said receptacle and said abutment such that said abutment is urged transversely of said longitudinal receptacle in locking engagement.   
     
     
       12. Apparatus as defined in claim 11 wherein said receptacle is defined by a generally cylindrical wall extending from a receptacle opening at a coronal end of said anchor means. 
     
     
       13. Apparatus as defined in claim 12 wherein said abutment means comprises a unitary member having an insertion end for inserting said abutment into said bore of said anchor means, an internal bore and a receiving end, said insertion end comprising an oblique bearing surface having one or more symmetrical protrusions. 
     
     
       14. Apparatus as defined in claim 13 wherein said locking means comprises a wedge nut and a longitudinally oriented screw, said wedge nut having a terminal end, a threaded cylindrical bore and a receiving end, said receiving end having a bearing surface complimentary to said bearing surface of said abutment such that said receiving end of said wedge nut and said insertion end of said abutment abut along said bearing surface. 
     
     
       15. Apparatus as defined in claim 14 wherein said screw extends through said internal bore of said abutment engaging at said receiving end of said wedge nut said threaded cylindrical bore of said wedge nut such that rotation of said screw urges said wedge nut against said abutment transferring lateral force across said bearing surface. 
     
     
       16. Apparatus as defined in claim 15 wherein said abutment means comprises a unitary member having an insertion end adapted for insertion into said bore at a coronal end of said anchor means, said abutment having an internal bore and smooth outer walls at said insertion end terminating at an oblique bearing surface formed transversely of said internal bore at insertion end, and an attachment post extending beyond said coronal end for attachment of a prosthesis thereto. 
     
     
       17. Apparatus as defined in claim 16, wherein said lock means comprises a locking element disposed between said oblique bearing surface and said cylindrical wall and connected to said abutment means by a threaded member extending through said internal bore such that rotation of said threaded member urges said locking element axially within said axial bore in wedging engagement between said abutment and said cylindrical wall. 
     
     
       18. Apparatus as defined in claim 17 wherein said locking element is a wedge nut having a bearing surface formed obliquely to said threaded member for confronting engagement with said oblique bearing surface of said abutment means such that rotation of said threaded member urges said wedge nut against said oblique bearing surface such that a component of the force applied in rotation of said threaded member is transferred to urge said nut and insertion end laterally against said cylindrical walls. 
     
     
       19. Apparatus as defined in claim 18 wherein said threaded member has a laterally extending shoulder for engagement with a laterally extending seat formed in said internal bore. 
     
     
       20. Apparatus as defined in claim 19 wherein said wedge nut has a plurality of angularly space protrusions formed thereon for engagement in selected one of a plurality of indexing grooves formed in said wall of said axial bore. 
     
     
       21. An implant system for attaching a prosthesis to an osseous structure comprising: a. an anchor to serve as a receptacle having a cylindrical smooth-walled axial bore with a terminal end and an entrant end;   b. an abutment having an insertion end for mating with said axial bore of said anchor, an internal cylindrical bore, and a coronal end, said insertion end having a bearing surface including at least one set of symmetrical protrusions, wherein said insertion end of said abutment further comprises two triangular symmetrical prongs having four bearing surfaces; and   c. locking means engageable with said abutment for locking said abutment to said anchor by lateral expansion of said locking means, said locking means having four opposing bearing surfaces.   
     
     
       22. An implant system as in claim 21 wherein said locking means comprises a wedge nut cylindrically shaped having an insertion end, a superior end, and a threaded axial bore for receiving said abutment, the walls of said axial bore having symmetrically aligned triangular slits initiating at said superior end and terminating prior to the insertion end of said wedge nut for receiving said symmetrical prongs therein. 
     
     
       23. An implant system as in claim 22 wherein said cylindrical wedge nut is connected to said abutment with a threaded screw extending through said axial bore of said abutment engaging with said threaded axial bore of said wedge nut such that rotation of said screw urges said wedge nut against said abutment imparting a lateral force against said cylindrical axial bore of said anchor. 
     
     
       24. An implant system as described in claim 23 wherein said locking means comprises a locking element disposed between said bearing surface and said cylindrical wall and connected to said abutment by a threaded member extending through said axial bore of said abutment such that rotation of said threaded member urges said locking element axially within said cylindrical smooth-walled axial bore of said anchor. 
     
     
       25. An implant system as described in claim 24 wherein axial movement of said locking element against said abutment causes expansion of said locking element against said cylindrical smooth-walled axial bore.